Crankshaft journal grinder



S. GOLTEN CRANKSHAFT JOURNAL GRINDER May 24, 1960 2 Sheets-Sheet l Filed Sept. 27. 1956 /NVENTOR SGURD GOLTEN awwv/ ATTORNEY.

May 24, 1960 s. GoLTl-:N 2,937,479

CRANKSHAFT JOURNAL GRINDER Filed Sept. 27. 1956 I 2 Sheets-Sheet 2 .A from/Ey UnitedStates Patent'(lF 2,937,479 cnANKsHAFrJoURNAL GRINDER SigurdvGolten, 455 Carroll St., Brooklyn, N.Y.

Filed Sept. 27, 1956, Ser. No. 612,451

6 Claims. (Cl. 51-241) This invention relates to crankshaft journal grinder. Its principal object is to provide improved means for regrinding main and crankpin journals in large marine engines without removing the crankshaft from the engine and without laying up the ship for more than a few days. (When journals have been scored heretofore, it has 'been usually necessary to lay up the ship for weeks while the engine is torn down and the crankshaft removed forregrinding.)

A crankshaft consists of a series of main and crankpin journals connected by fillets to crank cheeks. In practice the journal bearings run on the cylindrical portions of the journals, the ends of the bearings being chamfered to provide clearance so that they never touch the fillets. When the cylindrical portions of the journals become worn or damaged, the damage ordinarily does not extend to the fillets. An object of this invention is to use the fillets as the reference surfaces in regrinding crankshaft journals. Another object is to use the engine frame to position the grinding wheel, while the crankshaft is turned in its other bearings, to regrind a main journal without removing the crankshaft from the engine.

In feeding the grinding wheel into grinding contact with the journal, if the -feed were positive and the operator should feed too rapidly at the instant of contact, the grinding wheel would gouge the journal. A11 object of this invention is to provide means such as gravity or spring pressure for feeding the grinding wheel into contact, permitting the wheel to stop feeding or back away from the journal if the operator should release the feed too rapidly.

These and other objects of the invention will be apparent `from the following specification taken in connection'with the drawings in which Fig. 1 is an elevational view of a crankshaft with sectional views of two modifications of the invention;

Fig. 2 is an end view partly in section taken on the line 2-2 of Fig. 1;

Fig. 3 is a side view of a portion of Fig. 2, taken on the line 33;

Fig. 4 is an end view partly in section taken on the line 4-4 of Fig. 1;

Fig. 5 is a sectional view of a portion of the mechanism, taken on the line 5-5 of Fig. 4; and

Fig. 6 is an end view partly in section taken on the line 6-6 of Fig. 1.

Referring to the drawings, crankshaft 10 is mounted in bearings in fra-me 11. Crankshaft 1t) comprises the usual series of main journals and crankpin journals connected by fillets 23 to cheeks 14.

Referring to Figs. 2 and 3 and corresponding portion of Fig. 1, after -removing the main `bearing cap and the main bearings, a false half-'bearing 12, with the cylindrical portion of the bearing removed, may be slipped into place to support the shaft on fillets 23 during the regrinding operation. Then two-part fixture 15-16 is ice clamped to false half-bearing 12 by studs A18.. Fixture" 16 is provided with VV-ways 17. Universal j oint 21 is slidably mounted in V-ways 17, and operablyj supports carriage 24 in a manner preventing rotation of carriage Y 24 while permitting it to be swung about univeral joint` 21 and moved longitudinally in V-ways 17. Motor 25 is clamped in carriage 24j and carries cupwheel 26. Car-L riage 24 is provided with handle 28 and feed screw 27 operably bearing on top surface 19 of fixture 15,

ln regrinding a main journal, while crankshaft 10 (supported by other main bearings and by fillets 23 bearing on false half-bearing 12) is turned by the starting engine or other means, motor 25 drives cupwheel 26, and the operator releases feed screw 27 until cupwheel 26 comesv into grinding contact with journal 20, fed by gravity.`

Operator can move carriage 24 in V-ways 17and by swinging it about universal joint 21 to cause cupwheel 26 to move tangentially and longitudinally relative to journal 20, until the entire surface of journal 20 has been re-v ground precisely cylindrical relative to the axis of fillets 23, the axis of rotation. The corner of cupwheel 26 may be dressed or rounded otf to blend the new cylindrical surface of journal l20 in fillets 23.

Referring to Figs..4, 5 and 6, and the corresponding portion of Fig. 1, after removing the crankpin bearings and pushing the connecting rod out of the way, a threepart fixture 31-32-33 is clamped around crankpin journal 30 by bolts 34. Ball-ended screws 35 inclined at 45 Y degrees in fixture 31-33 are held in contact with fillets 23 by spring-pressed ball-ended plungers 36 in fixture 32.

` The pairs of ball-ends of screws 35 and plungers 36 are:

spaced about crankpin 30 to locate and hold fixture 31-32-33y concentric therewith while leaving itfree' to rotate about the axis of crankpin journal 30.

Yoke 37 is pivoted in fixture 33. V-way block 38 may rock on trunnions 39 in yoke 37. Yoke 37 and V-way.

block 38 form a runiversal joint. One end of carriage 40 is slidable in the V-ways of block 38. Grinding spindle 41 is operable in suitable bearings in carriage 40..`

On one end of spindle 41 is cupwheel 42 and von the other end, bevel gear 43v meshing with gear 44 on the shaftv of motor 45 secured to carriage 40. Feed screw 46 is..

threaded in the carriage 40 and bears on the upper plane face of fixture 31 and is pressed against it by spring 47`y coacting with C-clamp, 48 hooked around fixture 31.v

Handle 49 is provided on carriage 40,

In regrinding crankpin journal 30, motor 45 drives gear'` 44 which drives gear 43"on spindle 41 which drives cup-, wheel 42. The operator may unscrew feed's'crew 4'6 un-' til cupwheel 42 comes into grinding contact with journal 30, fed by spring 47, and may use handle 49 to swing Vcarriage 40 about the axis of yoke 37 or move it longitudinally in V-ways of block 38, causing cupwheel 42 to move in a plane parallel to the axis of crankpin journal 30, while crankpin journal 30 is rotating relative to the grinding mechanism until the entire cylindrical surface of journal 30 has been reground precisely cylindrical relative tothe axis of fillets 23. If desired, instead of rotating crankpin journal 30 relative to the grinding mechanism, shaft 10 may remain stationary while the entire grinding mechanism is caused to rotate about Y A stood that changes may be made in the construction and raient-d May 24.19.60,'.

in the arrangement of the mechanism and that changes may be made in the method of regrinding journals without departing from the spirit or scope of the invention as expressed in the following claims.

I claim:

1. A mechanism for grinding a crankshaft journal having a cylindrical portion connected by fillets to crank cheeks, said mechanism comprising a fixture operably mounted around said journal, three pairs of ball-ended rods angularly disposed in said fixture and spaced about said journal to bear in said fillets and hold said fixture operably coaxial with said journal, a carriage operably mounted on said fixture, a grinding cupwheel, a motor for driving said cupwheel and mounted on said carriage, and means for feeding said grinding cupwheel into grinding contact with said journal and for moving said cupwheel in a plane tangent to said journal while rotating said mechanism about said journal until the entire journal has been ground precisely and coaxially with respect to its axis.

2. A mechanism for grinding a crankshaft journal having a cylindrical portion connected by fillets to crank cheeks, said mechanism lcomprising a fixture operably mounted around said journal, three pairs of ball-ended rods angularly disposed in said fixture and spaced about said journal and bearing in said fillets, one of said pairs being spring-pressed, said pairs-of ball-ended rods holding said fixture operably centered with respect to said journal, a carriage operably mounted on said fixture, a grinding cupwheel, a motor carrying said grinding cupwheel and mounted on said carriage, and means for feeding said cupwheel into grinding contact with said journal and for moving said cupwheel in a plane parallel to the axis of said journal while rotating said mechanism about said journal until the entire journal has been ground coaxially therewith in one operation.

3. In connection with an engine having a crankshaft mounted therein, in mechanism for grinding a crankshaft journal having a cylindrical portion connected by fillets to crank cheeks, a fixture operably centered on said fillets and comprising a grinding cupwheel, a motor for driving said cupwheel, and means for allowing said cupwheel to be fed into grinding contact with said journal and for moving said cupwheel in a plane parallel to the axis of said journal while rotating said fixture continuously more than one revolution about said journal until the entire cylindrical surface of said journal has been reground precisely coaxially therewith.

4. In connection with an engine having a crankshaft t mounted therein, a mechanism for grinding a crankshaft journal having a cylindrical portion connected by fillets to crankcheeks, said mechanism comprising a fixture operably centered on said fillets, a carriage operably mounted on said fixture, a grinding cupwheel, a motor carrying said cupwheel and mounted on said carriage with the cupwheel axis substantially normal to said journal, means for feeding said cupwheel into grinding contact with said journal and for moving said cupwheel in a plane tangent to said journal, and means for continuously rotating said fixture more than one revolution about said journal.

5. In connection with an engine having a crankshaft comprising main and crankpin journals connected by crankcheeks, the cylindrical portions of whose journals have been worn or scored leaving undamaged ring areas at the ends thereof: a mechanism for regrinding one of said journals without removing the crankshaft from the engine, said mechanism comprising a frame member operably mounted on the undamaged ring areas at the ends of said journal; a carriage operably mounted on said frame memberg. a motor mounted on said carriage; a cupwheel driven by said motor the plane grinding face of said cupwheel being tangent to said journal; means for moving said cupwheel in a plane tangent to said journal; and means for rotating said frame member continuously more than one revolution about said journal until the entire journal has been reground coaxially with said undamaged ring areas.

' 6. In connection with an engine having a crankshaft comprising main and crankpin journals connected vby crankcheeks, the cylindrical portions of whose journals have been worn or scored leaving undamaged ring areas at the ends thereof; a mechanism for regrinding one of said journals without removing the crankshaft from the engine, said mechanism comprising a frame member operably mounted on the undamaged ring areas at the ends of said journal; a carriage operably mounted on said frame member; a motor mounted on said carriage, a cupwheel driven by said motor the plane grinding face of said cupwheel being tangent to said journal; means for feeding said grinding cupwheel into grinding contact with said journal; and means on said carriage for moving said cupwheel in a plane tangent to said journal while rotating said mechanism continuously more than one revolution about said journal until the entire cylindrical portion thereof has been reground in one operation.

References Cited in the file of this patent UNITED STATES PATENTS 1,523,890 Parkinson Ian. 20, 1925 2,130,003 Fuglie et al Sept. 13, 1933 2,277,144 Petersen Mar. 24, 1942 2,574,228 Sawyer Nov. 6, l 2,599,954 Tibbs June l0, 1952 2,755,609 Sylvester July 24, 1956 

